This specification relates to monitoring proximity for tracking members of a group.
In crowded locations, particularly in locations with distractions (e.g., shopping malls or museums) families, tourist groups, or other groups can have difficulty maintaining contact with one another or keeping track of where others in the group are located. Communication by mobile phone is one option for staying in contact, but not everyone in the group necessarily has a mobile phone, particularly if some members of the group are young or otherwise require closer monitoring. Systems exist for monitoring location of objects using, for example, radio frequency identification (RFID) techniques, such as in the shipping industry or for purposes of determining whether an object leaves a defined perimeter, but such systems are generally not conducive to monitoring people particularly in large or public areas and require significant infrastructure support.